Abstract:

After coring,ice sampling strategies and preliminary interpretations require a preliminary understanding of age depth profiles of the core,which means the well established time scales are necessariated. According to ice flow state,temperature distribution,mass balance and dynamic characteristics of Low Dome on Collins Ice Cap,revealed by observational data collected in situ for more than one year,Dansgaard Johnsen model and isothermal ice flow models for n=3 are adopted respectively to calculate the time scales of a 80. 2m ice core.Our calculation show a very approximate time scale of the core,at depth of 10m above the bedrock,ice dating of 1879 a and 1854 a B.P.are obtained by these two models respectively.The maximum error between two model calculation is no more than 2% at each depth of the ice cap.Comparisons with the chronical records of the volcanic ash layers contained in the middle upper part of the core suggest an age error less than 3%.